Hours needed to consume a drink in small amount (7)

'small amount' is the definition.
'ha'p'orth' can be an answer for 'amount' (ha'p'orth is a kind of amount). I'm not certain of the 'small' bit.

'hours needed to consume a drink' is the wordplay.
'hours' becomes 'hh' (an abbreviation for hour written twice).
'needed to consume' is an insertion indicator.
'drink' becomes 'port' (port is a kind of drink).
'a'+'port'='aport'
'hh' placed around 'aport' is 'HAPORTH'.

'in' acts as a link.

Can you help me to learn more?